Expansion closure plug



1954 w. F. BORGES ETAL EXPANSION CLQSURE PLUG Filed Sept. 20, 1951 -7II%ENTORS y 7 Q Patented Jan. 12, 1954 EXPANSION CLOSURE PLUG Walter Borges and Vernon W Goss, Milwaukee,

Wis assignors to Wrou corporation of Wisconsin ght Washer Mfg. 00., 9.

Application September 20, 1-951, Serial No. 247,464

.8 Claims. .1

This invention relates'to improvements the art of closing cylindrical openings and more particularly openings .such as the core holes in engine cylinder blocks or other openings where similar problems are present.

The Welch plug shown in Patent No. 1,058,210 has been long used by the engine industry. This type of plug has not been entirely satisfactory because of the fact that there is no assurance against leakage. In addition, Welch type plugs have, on occasion, dropped out of core holes completely, thereby permitting the cooling water of the engine to escape with resulting overheating of the engine.

With the advent of harder metals for use in en glne cylinder blocks and heads, the problem of closing core holes has become more serious, since the Welch type of plug is less efiective when used in blocks of hard metal than when used in blocks of softer material. Additional problems have also arisen, in recent years, because of the fact that high speed, mass production machinery frequently fails to perform accurate boring and other machining operations as compared with the operations heretofore performed by prior slow speed machines. As a result, core holes in present day engine blocks are frequently formed with chatter marks and other imperfections.

With the above in mind, it is a general object of the present invention to provide improvements in the art of closing cylindrical openings, whereby a fluid-tight, permanent closure is [provided even though the opening is formed in relatively hard metal, and even though it has surface imperfections such as tool marks. I I

A further object of the invention is to provide an improved plug for the purpose described, said plug being in the form of a concave-convex disc having its peripheral edge formed with a circumferential. groove so located as to provide a pair of circumferential annular beads. said beads being adapted to be upset by engagement with the wall of the opening as a result of expanding deformation of the disc, with said beads sealingly engaging the wall of the opening and conforming with any irregularities in the wall surface.

A further object of the invention is to provide an improved device of the class described having a circumferential groove which is filled with flowable material to aid in forming a permanent seal.

A further object of the invention is to provide an improved device of the class described which can be applied in the same manner as conventional plugs, no special tools being required.

A further object of the invention is to provide 2 an lmproved'device of the class descrlbed'whl'c'h is simple in construction, easy to manufacture, and otherwise well adapted for the purposes described.

With the above and other objects in view, the invention consists of the improvements in the art of closing cylindrical openings, and all of the steps, parts and combinations incident thereto, as set forth in the claims, and all equivalents thereof.

In the drawing accompanying and forming a part of this specification, wherein two forms of the invention are shown, and wherein like characters of reference indicate the same parts in all of the views: Y

Fig. l is a vertical sectional view showing the preferred form of plug, prior to deformation, positioned in a cylindrical opening such asthe core hole of an engine cylinder block;

Fig. 2 is an enlarged fragmentary vertical sectional view'of a portion of the device shown in Fig. 1;

Fig. 3 is an enlarged fragmentary vertical sectional view of the device of Fig. 1 after thelatter has been expandingly deformed into sea-lin engagement with the wall of the opening;

Fig. 4, isan enlarged fragmentary vertical sectional view similar to Fig. 2 and showing aportion of a. modified form of plug;

Fig. 5 is an enlarged fragmentary vertical sectional view similar to Fig. 3 showing the modified form of plug deformed into sealing engagement with the wall of an opening; and

Fig. 6 is a view similar to Fig. 2 illustrating an additional modification.

Referring more particularly to Figs. 1 and 2, the numeral I0 indicates a concavo-convexdisc of suitable metal such as low carbon steel which is deformable only under substantial pressure, the disc having a substantially cylindrical peripheral edge surface II. For certain requirements other material such as brass may be used for the disc. Formed inthe peripheral surface I I intermediate the width thereof, is a circumferential-1y extending groove I2 which provides a pair of spaced peripheral, circumferentially extending annular beads or flanges I3 and Id. In the usual automotive use, the width ofthe groove 12 is preferably one-third of the width of the, edge surface II. but; this is not necessarily true. For automotive uses, the discs usually vary from about one-half inch to about three and onerhalf inches in diameter and the thickness is prefer, ably one-fourth of an inch or less. When the disc has 5 of an inch thickness the groove is prefers The disc I0 is expanded into position in the bore I! by a blow from a hammer or other suitable instrument which deforms it to the more flattened shape shown in Fig. 3. Asthe disc 1 B 'is thus expanded, the beadsl3 and I4 are-forced are upset against the bore wall to sealingly engage the surface and conform with surface irregularities. If a fiowable material is employed in the grooves, as heretofore described in connection with Fig. 4, such material will aid in forming a permanent and positive seal. It is, of course, practical to utilize a greater or lesser number of grooves than is illustrated inFig. 6.

It is to be understood that the invention disclosed herein is not limited to the details of construction and arrangement of parts illustrated in the accompanying drawing, but that various changes and modifications may be made without "departing from the spirit of the invention. All

radially outwardly under extreme pressure into contact with the wall surface of the bore ll. The

beforementioned extreme pressure causes up- 4 setting of the metal of the beads 13 and I4 against the bore wall, forcing said. beads to sealingly engage the surface of the bore I! and conform with any surface irregularities.

Figs. 4 and 5 show a modified form of disc 10' which is substantially identical with the disc to.

The parts of the disc H) which are indicated by primed numerals are similar to corresponding parts of the disc (0 indicated by unprimed numerals. The disc [0' is formed with a circum ferential groove l2 in its edge surface I I, which groove is entirely filled with flowable material 9.

The flowable material is preferably a solid although it need not necessarily be so. It usually is important that the flowable material be softer than the material of which the disc is made.

Lead, copper, brass, lead-tin alloys, and nonbrittle plastic materials of a type which are flow- ,able only under relatively high pressure and which are stable under conditions of use such as those which are to be encountered maybe employed. It is to be emphasized, however, that the broader aspects of this form of the invention contemplate the use of the groove as a confining carrier for any flowable material which has sealing characteristics suitable for the particular requirement. r

.treme pressure is also exerted on the fiowable material l8, and the latter then flows into any irregularities in the wall surface of the bore l1. Just as in the case of thebeads l3 and M of the disc 10, the beads 13' and I4, upon being upset, conform to the surface contours of the bore H and, aided by the flowable material I9, form a permanent and positive seal.

In Fig. 6 an additional modification is illustrated. Here the disc [9, which is substantially the same as the discs I 0 and I0 is formed with a plurality of circumferential grooves 20. In the illustrated embodiment, there are three grooves, and as a result, there are four circumferential beads 2|. This form of the invention is used in the same way as heretofore described and may be used with or without a flowable material in the grooves 20, Fig. 6 showing such'iiowable material. When the disc is expanded into position in a bore such as the bore ll of Fig. 1, the beads 21 of such changes as well as alternative uses are contemplated as may come within the scope of the claims What we claim is:

l. A closure for a cylindrical opening, comprising: a concavo-convex disc of material which is deformable under substantial pressure, said disc having a substantially cylindrical peripheral edge surface, said edge surface being formed with an annular groove; and a normally solid flowable sealing material filling said annular groove to a point where it is substantially flush with said cylindrical edge surface. 1

2. A closure for a cylindrical opening," comprising: a concavo-convex disc of material which is deformable under substantial pressure; a pair of spaced radially outwardly directed annular beads formed on the peripheral edge of said disc. there being an annular groove between said beads, the outer diameters of said beads being substantially equal to the diameter of the opening to be closed; and an annular ring of normally solid flowable sealing material encircling said disc and normally confined between said beads and substantially filling said annular groove to a point where it is flush with the outer diameters of said beads.

3. A; closure for a cylindrical opening, comprising: a concavo-convex disc of material which is deformable under substantial pressure; a pair of spaced radially outwardly directed annular beads formed on the peripheral edge of said disc, there being an annular groove between said beads, the outer diameters of said beads being substantially equal to the diameter of the opening to be closed; and an annular ring of material which is normally solid but which is softer than the material of the disc encircling said disc and normally confined between said beads and substantially filling said annular groove to a point where it is flush with the outer diameters of said beads.

4. A closurefor a cylindrical opening, com!- prising: a concave-convex disc of material which is deformable under substantial pressure; a pair of spaced radially outwardly directed annular beads formed on the peripheral edge of said disc. there being an annular groove between said heads, the outer diameters of said beads being substantially equal to the diameter of the opening to be closed; and an annular ring of leadcontaining sealing material encircling said disc and normally confined between said beads and substantially filling said annular groove to a point where it is flush with the outer diameters of said beads.

5. In combination: a member having a cylindrical opening; a concavo-convex disc of material which is deformable under substantial pressure seated in said opening, said disc having a pair of spaced outwardly directed annular beads on its peripheral edge which are in tight partially deformed contact with the wall of said opening, there being an annular groove between said beads and there being a normally hard sealing material of a type which is fiowable under pressure filling said groove and being also in a state of having overfiowed said groove so that it fills irregularities which are located between said beads and wall and coacts with said beads in forming a complete seal.

6. In combination: a member having a cylindrical opening; a concavo-convex disc of material which is deformable under substantial pressure seated in said opening, said disc having a pair of spaced outwardly directed annular beads on its peripheral edge which are in tight partially deformed contact with the wall of said opening, there being an annular groove between said beads and there being a lead-containing sealing metal filling said groove and also in a state of having overfiowed said groove so that it fills irregularities which are located between said beads and wall and coacts with said beads in forming a complete seal.

7. In combination: a member having a cylindrical opening; a concavo-convex disc of material which is deformable under substantial pressure seated in said opening, said disc having a pair of spaced outwardly directed annular beads on its peripheral edge which are in tight partially deformed contact with the wall of said opening, there being an annular groove between said beads and there being sealing material formed of metal which is softer than the metal of the disc and which is fiowable under pressure filling said groove and also in a state of having overfiowed said groove so that it fills irregularities which are located between said beads and wall and coacts with said beads in forming a complete seal.

8. In combination: a member having a cylindrical opening and having a counterbore communicating with an end of said opening, there being a shoulder between said opening and counterbore; a concavo-convex disc of material which is deformable under substantial pressure seated in said counterbore against said shoulder with its concave side facing inwardly, said disc having a pair of spaced outwardly directed annular beads on its peripheral edge which are in tight, partially deformed contact with the wall of said counterbore, there being an annular groove between said beads and there being sealing material of a type which is flowable under pressure filling said groove and also in a condition of having overfiowed said groove so that it fills irregularities which are located between said beads and wall to coact with said beads in forming a complete seal.

WALTER F. BORGES. VERNON W. GOSS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 793,307 Lachman June 27, 1905 808,567 McManus Dec. 26, 1905 1,058,210 Welch Apr. 8, 1913 1,306,641 Steenstrup June 10, 1919 1,730,377 Northrup Oct. 8, 1929 1,837,345 Thomas Dec. 22, 1931 1,974,150 Creveling Sept. 18, 1934 2,265,951 Miner Dec. 9, 1941 FOREIGN PATENTS Number Country Date 626,415 Great Britain July 14, 1949 

